Tire pressure indicator



Oct. l5, 1940. R, R, BlRCHFlELD 2,218,143

TIRE PRESSURE INDICATOR Filed DBC. 11, 1959 2 Sheets-Sheet 1 i INVENToR. BY

ATTORNEYS.

R. R. BIRCHFIELD TIRE PRESSURE INDICATOR Filed Dec. 11, 1939 2 Sheets-Sheet 2 .fckfivela3 IN VEN TOR.

A TTORNEYS.

oct. 15, 1940.

Patented Oct. 15, 1940 UNITED STATES TENT OFFICE 1 Claim.

This invention aims to provide novel means whereby the pressure in the tires of the wheels of a vehicle can be ascertained readily at a glance, from a fixed place on the vehicle.

It is within the province of the disclosure to improve generally and to enhance the utility of devices of that type to which the present invention appertains'.

With the above and other objects in view, which will appear as the description proceeds, the invention resides in the combination and arrangement of parts and in the details of construction hereinafter described and claimed, it being understood that changes in the precise embodi- 3 ment of the invention herein disclosed, may be made within the scope of what is claimed, without departing from the spirit of the invention.

In the drawings:

Fig. 1 shows, in elevation, front and rear wheels of a Vehicle wherein the device forming the subject matter of this application has been incorporated, parts being in section;

Fig. 2 is a sectional view showing the means whereby a passage of air from the Vehicle tire to the indicating mechanism is made possible;

Fig. 3 is an elevation of the structure shown in Fig. 2, parts being broken away.

The numeral I marks a wheel body, carrying an inatable tire 2. There are holes 3 in the wheel body I.

Securing elements 4 attach a ring or distributor 5, and an annular member 6, such as a brake drum, to the wheel body I. The numeral 1 marks a closure for the brake drum 6. The closure is secured to an aXle housing 8. An axle 9 is mounted to turn in the axle housing 8, the ring or distributor 5, and consequently the wheel body I and associated parts, being secured to the axle.

In cross section, the distributor 5 is troughshaped, as Fig. 2 will show. The distributor 5 has an inwardly projecting annular flange I and an inwardly projecting annular flange Il. The

flanges Ill and Il form an annular air passage |2 in the distributor 5. A conduit I4, which may be a tube, exible or otherwise, leads through one of the holes 3 in the wheel body I. One end of the conduit III is secured to the distributor and communicates with the passage I2. The opposite end of the conduit I4 is secured to the wheel body I and communicates with the tire 2. A clamp ring I5 is threaded on the distributor 5. A fixed bearing and air delivery member I6 is provided, and in order that it may be prevented from rotating with the wheel and the ring 5, the member I6 is connected by brackets II, or by any other appropriate means, to the fixed closure 'I for the brake drum B.

The delivery member I6 extends between the flanges I0 and II of the distributor 5. The air deliveryl member I6 has an outwardly projecting ange I8, disposed opposite to the flange I0 of the distributor 5, and an inwardly projecting annular fiange I9, disposed opposite to the flange on the distributor 5. The flanges I8 and. I0, and I9 and Il, form raceways, in which ball bearings 2|) are mounted. For the prevention of the escape of air, Washers 2| are located within and without the delivery member I6, one set of Washers bearing against the ange I8, and the .other set of washers bearing against the flange I9. The clamping ring I5 exerts pressure on the washers 2|.

For the lubrication of the balls in the ball races, the ball races are connected by a duct 22 in the air delivery member I6. of the distributor 5 has a duct 23, leading to one of the ball races. One end of a conduit 24 is secured to the distributor 5 and communicates with the duct 23. The opposite end of the conduit 24 extends through vone of the holes 3 in the wheelbody I, and is closed by a cap 25, removably mounted in place. The delivery member I5 is supplied with a transverse duct 26, communicating at one end The outer wall with the passage I2 in the ring or distributor 5.

The opposite end of the duct 26 communicates with a nipple 2l on the delivery member I6, the nipple carrying a coupling 28 joined to an air conduit 29, which extends forwardly to a pressure gauge 30, mounted on the instrument board 3| of the vehicle, or elsewhere.

All wheels of the vehicle are equipped in the manner hereinbefore specified, and, noting that the numeral 32 in Fig. 1 designates the front axle of the vehicle, it will be obvious that the front wheels as well as the rear wheels fall within the eld of operation of the device.

Air pressure in the tire 2 passes by way of the conduit III to the channel I2 of the ring or distributor 5 on the wheel I. From the passage I2, air traverses the duct 26 in the delivery memy a conduit leading from the bore to the indicator,

means for holding the delivery member against rotation, the distributor and the delivery member having oppositely projecting flanges defining races, the delivery member having a duct Connecting the races, anti-friction bearings in the races, packings assembled With the delivery member and disposed opposite the races, means on the distributor for holding the packings, and means for supplying a lubricant to the packings,

by Way of the races, the duct, and the interior of l0 the distributor. v

' ROY R. BIRCHFIELD. 

